Invasion Of Connective Tissue Research Articles

Comparison of Mast Cell Count in Oral Epithelial Dysplasia and Squamous Cell Carcinoma.

Squamous cell carcinomas (SCCs) and premalignant disorders such as leukoplakia are common oral cavity lesions. Although these lesions are epithelial in nature, they are also associated with juxta-epithelial chronic inflammation. Mast cells play a significant role in inflammation initiation and propagation. Previous studies have yielded conflicting results in this field. Therefore, this research aimed to assess the number of mast cells in oral SCC and dysplastic leukoplakia and explore their possible role in these lesions. In this retrospective cross-sectional study, sixty-three archival cases, including 22 OSCCs, 28 dysplastic leukoplakias as epithelial dysplasia (ED), and 13 normal oral mucosal tissues, were examined for mast cells, using toluidine blue staining. Hotspot areas were identified at 10× magnification and mast cells were counted in 5 fields at 40× magnification. The average cell numbers were calculated, and the severity of inflammation was scored. Statistical analysis was performed using SPSS statistical software 20, including One-way ANOVA, Two-way ANOVA, paired-t test, and independent t-test. p Value < 0.05 was considered significant. Among the 51 pathologic lesions, 54.9% were males and 45.1% were females, with a mean age of 56.34±15.35 years. The most common locations were the tongue and buccal mucosa. The mast cell count was significantly lower in SCC compared to ED (p= 0.009). There was no correlation between mast cell count and inflammation score (p= 0.345). In this study, the mast cell count was higher in ED compared to OSCC, suggesting an increase in these cells during the pre-malignant stages. However, the number of mast cells decreased after connective tissue invasion and microenvironmental changes occurred.

278. PROPOSED REVISION TO THE DESCRIPTION OF T3 FOR ESOPHAGEAL CANCER: REMOVAL OF “ADVENTITIA”

Abstract Background T3 is an important depth for esophageal cancer to target for surgical cure. According to the Union for International Cancer Control (UICC), T3 is defined as tumor invading the adventitia. However, it remains unclear what structures the adventitia refers to. In fact, tumors that do not directly invade adjacent organs have been classified as T3, even if they extend through the adventitia. Furthermore, in tumors arising at the esophagogastric junction (EGJ), it is difficult to determine the border with the subserosa that defines T3 of the stomach. Our aim was to revise the description of T3 in esophageal cancer. Methods The Union for International Cancer Control T-classification was reviewed from a histologic, pathologic, and embryologic perspective. Analysis of endoscopic ultrasound images, review of intraoperative images, and detailed observation of surgical specimens were followed by a review of the literature. Results Histologically, the adventitia is the extramural adipose connective tissue of the digestive tract and serves as a conduit for blood vessels, lymphatics, and nerves. The esophageal adventitia is further surrounded by connective tissue of adjacent organs, such as the tissue around the trachea, the tissue around the descending thoracic aorta, the pulmonary ligament, and the tissue on the diaphragm (Fig. 1a). In the 2022 revision of the Japanese Esophageal Society, resectable borderline cases in which adjacent organ invasion cannot be excluded by preoperative imaging were subclassified as borderline resectable T3 (T3br). From another perspective, this is a clinically reasonable criterion that not only adventitial invasion, but also invasion of connective tissue associated with adjacent organs is classified as T3. Beyond the EGJ, the adventitia is covered by mesothelium in the peritoneal cavity and leads to the subserosa. Endoscopic ultrasound revealed the fatty tissue of the adventitia as a highly echogenic layer on the surface of the muscularis propria, which continues uninterrupted beyond the EGJ into the stomach, indicating that the adventitia is connected to the subserosa. Intraoperative images showed that the descending posterior trunk of the vagus nerve and its associated vessels pass through the adipose tissue surrounding the esophagus in the esophageal hiatus (Fig. 1b). Thus, the ambiguity in the T-classification of esophageal cancer is not resolved as long as T3 is defined by the adventitia. In practice, however, physicians may have classified tumors as T2 if confined to the muscularis propria, T4 if invading adjacent organs, and T3 if neither. Conclusion We suggest that the description of T3 esophageal cancer be revised to read "tumor extends through the muscularis propria" rather than using the term "adventitia". This revision would clarify the depth criteria for determining the indication for surgical treatment not only for esophageal cancer, but also for EGJ carcinoma where the tumor center overlaps the gastric side.

Urokinase-Type Plasminogen Activator Receptor (uPAR) in Inflammation and Disease: A Unique Inflammatory Pathway Activator.

The urokinase-type plasminogen activator receptor (uPAR) is a unique protease binding receptor, now recognized as a key regulator of inflammation. Initially, uPA/uPAR was considered thrombolytic (clot-dissolving); however, recent studies have demonstrated its predominant immunomodulatory functions in inflammation and cancer. The uPA/uPAR complex has a multifaceted central role in both normal physiological and also pathological responses. uPAR is expressed as a glycophosphatidylinositol (GPI)-linked receptor interacting with vitronectin, integrins, G protein-coupled receptors, and growth factor receptors within a large lipid raft. Through protein-to-protein interactions, cell surface uPAR modulates intracellular signaling, altering cellular adhesion and migration. The uPA/uPAR also modifies extracellular activity, activating plasminogen to form plasmin, which breaks down fibrin, dissolving clots and activating matrix metalloproteinases that lyse connective tissue, allowing immune and cancer cell invasion and releasing growth factors. uPAR is now recognized as a biomarker for inflammatory diseases and cancer; uPAR and soluble uPAR fragments (suPAR) are increased in viral sepsis (COVID-19), inflammatory bowel disease, and metastasis. Here, we provide a comprehensive overview of the structure, function, and current studies examining uPAR and suPAR as diagnostic markers and therapeutic targets. Understanding uPAR is central to developing diagnostic markers and the ongoing development of antibody, small-molecule, nanogel, and virus-derived immune-modulating treatments that target uPAR.

The preliminary analysis of lymphatic flow around the connective tissues surrounding SMA and SpA elucidates patients’ oncological condition in borderline-resectable pancreatic cancer

BackgroundIn pancreatic ductal adenocarcinoma (PDAC), invasion of connective tissues surrounding major arteries is a crucial prognostic factor after radical resection. However, why the connective tissues invasion is associated with poor prognosis is not well understood.Materials and methodsFrom 2018 to 2020, 25 patients receiving radical surgery for PDAC in our institute were enrolled. HyperEye Medical System (HEMS) was used to examine lymphatic flow from the connective tissues surrounding SMA and SpA and which lymph nodes ICG accumulated in was examined.ResultsHEMS imaging revealed ICG was transported down to the paraaortic area of the abdominal aorta along SMA. In pancreatic head cancer, 9 paraaortic lymph nodes among 14 (64.3%) were ICG positive, higher positivity than LN#15 (25.0%) or LN#18 (50.0%), indicating lymphatic flow around the SMA was leading directly to the paraaortic lymph nodes. Similarly, in pancreatic body and tail cancer, the percentage of ICG-positive LN #16a2 was very high, as was that of #8a, although that of #7 was only 42.9%.ConclusionsOur preliminary result indicated that the lymphatic flow along the connective tissues surrounding major arteries could be helpful in understanding metastasis and improving prognosis in BR-A pancreatic cancer.

Comparison of the Stress Analysis To Obtain The Tensile Properties of Three Type-1 and Type-3 Collagen Membranes

The aim of this study is to evaluate the mechanical tensile strength for control and specification of three collagen membranes, cross-linked and non-cross-linked, as well as their stress–strain curve. The treatment of sequelae caused by destruction of the periodontal structure resulting from periodontal disease, especially the treatment of alveolar bone defects, known as guided bone regeneration (GBR), is generally aimed at restoring the periodontal insertion apparatus, with the possibility of structural support of membranes and/or barrier, and has been widely studied. Depending on the reaction to their biological environment, membranes can be grouped into two types: resorbable membranes, which, due to biological degradation, induce a tissue response that can negatively affect wound healing and complicate regeneration; and non-resorbable membranes, which have proven to be effective in preventing the invasion of connective and epithelial tissue in the healing area. Resorbable membranes have a high potential for application in periodontal and peri implant regeneration, which indicates collagen as the main extracellular component involved in processes, including cell migration and differentiation. Descriptive statistics of quantitative variables were made by calculating the mean, standard deviation, and standard error; the number of observations was also considered. Statistical inference was applied based on one-way analysis of variance (ANOVA) in the comparison of means in three types of membranes (Bioguide, Jason, and Lumina Dermal) for four dependent variables: elastic modulus (GPa), maximum load (N), breaking stress (MPa), and breaking strain (%). The mechanical characteristics of collagen membranes can be influenced by the action of glutaraldehyde, creating a cross-linking structure in the collagen matrix, thereby substantially increasing the mechanical properties of the membrane; on the other hand, this also increases cytotoxicity. Otherwise, the search for natural collagen membranes with good fixation properties is difficult, due to membrane standardization. Nonetheless, through dimensional and mechanical measurements, it is possible to mechanically qualify collagen membranes and compare them. When assessing the physical stress and tensile properties of the three membranes, high levels of mechanical strength were observed, especially in the Lumina Dermal membrane by Criteria Biomateriais, which presents higher rates based on the methodologies and tests applied, mainly when compared to other samples.

Modeling periodontal host-microbe interactions using vascularized gingival connective tissue equivalents

Gingival connective tissue and its vasculature play a crucial role in the host’s immune response against the periodontal microbiome and serve as a bridge between the oral and systemic environments. However, there is a lack of representative models that mimic the complex features of vascularized gingival connective tissue and its interaction with the periodontal microbiome, hindering our understanding of periodontal health and disease. Towards this pursuit, we present the characterization of vascularized gingival connective tissue equivalents (CTEs) as a model to study the interactions between oral biofilm colonizers and gingival tissues in healthy and diseased states. Whole-mount immunolabeling and label-free confocal reflectance microscopy of human fibrin-based matrix embedded with gingival fibroblasts and microvascular endothelial cells demonstrated the generation of bi-cellular vascularized gingival CTEs. Next, we investigated the response of the vascularized gingival CTEs to early, intermediate, and late oral biofilm colonizers. Despite colonization, the early colonizers did not elicit any significant change in the production of the cytokines and chemokines by the CTEs representative of the commensal and homeostatic state. In contrast, intermediate and late colonizers representing a transition to a diseased state exhibited connective tissue and vascular invasion, and elicited a differential immune response accompanied by increased monocyte migration. The culture supernatants produced by the vascularized gingival CTEs in response to early and intermediate colonizers polarized macrophages towards an immunomodulatory M2-like phenotype which activates and protects the host, while the late colonizers polarized towards a pro-inflammatory M1-like phenotype. Lastly, in silico analysis showed a high strength of associations between the proteins and transcripts investigated with periodontitis and vascular diseases. In conclusion, the vascularized gingival CTEs provide a biomimetic in vitro platform to study host-microbiome interactions and innate immune response in periodontal health and diseased states, which potentially paves the way toward the development and assessment of novel periodontal therapeutics.

Vimentin-mediated myosin 10 aggregation at tips of cell extensions drives MT1-MMP-dependent collagen degradation in colorectal cancer.

Colorectal cancer (CRC) is a high prevalence adenocarcinoma with progressive increases in metastasis-related mortality, but the mechanisms governing the extracellular matrix (ECM) degradation important for metastasis in CRC are not well-defined. We investigated a functional relationship between vimentin (Vim) and myosin 10 (Myo10), and whether this relationship is associated with cancer progression. We tested the hypothesis that Vim regulates the aggregation of Myo10 at the tips of cell extensions, which increases membrane-type 1 matrix metalloproteinase (MT1-MMP)-associated local collagen proteolysis and ECM degradation. Analysis of CRC samples revealed colocalization of Vim with Myo10 and MT1-MMP in cell extensions adjacent to sites of collagen degradation, suggesting an association with local cell invasion. We analyzed cultured CRC cells and fibroblasts and found that Vim accelerates aggregation of Myo10 at cell tips, which increases the cell extension rate. Vim stabilizes the interaction of Myo10 with MT1-MMP, which in turn increases collagenolysis. Vim depletion reduced the aggregation of Myo10 at the cell extension tips and MT1-MMP-dependent collagenolysis. We propose that Vim interacts with Myo10, which in turn associates with MT1-MMP to facilitate the transport of these molecules to the termini of cell extensions and there enhance cancer invasion of soft connective tissues.

V06-08 UPPER TRACT TUMOR EN BLOC ENUCLEATION: A NOVEL APPROACH TO THE DIAGNOSIS AND MANAGEMENT OF UPPER TRACT UROTHELIAL CARCINOMA

You have accessJournal of UrologyCME1 Apr 2023V06-08 UPPER TRACT TUMOR EN BLOC ENUCLEATION: A NOVEL APPROACH TO THE DIAGNOSIS AND MANAGEMENT OF UPPER TRACT UROTHELIAL CARCINOMA Joshua Jue and Noel Armenakas Joshua JueJoshua Jue More articles by this author and Noel ArmenakasNoel Armenakas More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003274.08AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: The identification of high grade disease and subepithelial connective tissue invasion (pT1 disease) are important prognostic factors which guide treatment options in upper tract urothelial carcinoma (UTUC). We aim to describe and demonstrate our novel en bloc enucleation technique for the endoscopic diagnosis and treatment of upper tract tumors. METHODS: We detail the instruments required for this procedure, as well as the surgical technique to perform an en bloc enucleation and specimen removal. Endoscopic video of a 2 cm renal pelvis tumor demonstrates all aspects of the technique, and histopathologic slides illustrate the diagnostic information obtained. RESULTS: A ureteral access sheath is inserted distal to the upper tract tumor, and a flexible ureteroscope is used to visualize the extent of upper tract disease and tumor characteristics. A 200 mm thulium fiber laser partially ablates the tumor surface to create an edge for tissue biopsy and post-ablation urine cytology. The tumor base is identified and the subepithelial connective tissue is carefully entered with low ablation laser settings. The correct tissue plane is extended by maintaining the ureteroscope in the subepithelial connective tissue and continuing the dissection along the entire width of the tumor base. Once the tumor is enucleated, a Nitinol stone retrieval basket is used to remove the specimen(s) and a ureteral stent is placed. CONCLUSIONS: En bloc enucleation is a safe technique that provides extensive histopathologic information in upper tract urothelial carcinoma. In cases where complete enucleation is not feasible, this procedure affords a mechanism for large caliber biopsies, enhancing diagnostic accuracy. This technique can be therapeutic in low grade and stage disease, but also offers a mechanism for large caliber biopsy if complete enucleation cannot be performed. Source of Funding: None © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e511 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Joshua Jue More articles by this author Noel Armenakas More articles by this author Expand All Advertisement PDF downloadLoading ...

Complete response to combination therapy using nivolumab and ipilimumab for metastatic, sarcomatoid collecting duct carcinoma presenting with high expression of programmed death-ligand 1: a case report

BackgroundCollecting duct carcinoma and sarcomatoid renal cell carcinoma are tumors with poor prognosis. Immune checkpoint inhibitors have been established as the standard treatment for advanced renal cell carcinoma. Some cases of remission of collecting duct carcinoma and sarcomatoid renal cell carcinoma have been reported using immune checkpoint inhibitor interventions. Specifically, sarcomatoid renal cell carcinoma expresses high levels of programmed death-ligand 1, an immune checkpoint protein, and immune checkpoint inhibitors have been reported to be highly effective for treating sarcomatoid renal cell carcinoma.Case presentationWe describe the case of a 70-year-old Japanese male who underwent radical right nephrectomy for a right renal mass identified on computed tomography. The pathological examination demonstrated that the renal mass was urothelial carcinoma and collecting duct carcinoma with sarcomatoid changes, and programmed death-ligand 1 was highly expressed with a tumor proportion score of more than 10%. There was no evident submucosal connective tissue invasion in the urothelial carcinoma component, and collecting duct carcinoma was diagnosed as primary cancer. The tumor–node–metastasis classification was pT3aN0, venous invasion 1, lymphovascular invasion 0, and Fuhrman nuclear grade 4. Two months after the nephrectomy, multiple metastases were observed in both lungs, the right hilar lymph node, and the S6 segment of the right liver lobe. We initiated first-line combination therapy with nivolumab (240 mg, fixed dose) and ipilimumab (1 mg/kg). One day after administration, the patient developed drug-induced interstitial pneumonia, thus we applied steroid injections. After one administration of immunotherapy, the metastatic lesion showed complete response within 6 months, which was maintained after 3 years.ConclusionWe report the first case of complete response to a single dose of combination therapy with nivolumab and ipilimumab for metastatic collecting duct carcinoma with sarcomatoid changes and high expression of programmed death-ligand 1. This case suggests high expectations for immune checkpoint inhibitors as treatment for sarcomatoid-transformed renal carcinoma tumors that express high levels of programmed death-ligand 1.

Fabrication of oxidized sodium alginate-collagen heterogeneous bilayer barrier membrane with osteogenesis-promoting ability

Guided bone regeneration technique is an effective approach to repair bone defects, in which a barrier membrane is essential. However, the collagen barrier membranes commonly used lose stability quickly, leading to connective tissue invasion and failure of osteogenesis. Herein, we presented an oxidized sodium alginate (OSA)-collagen heterogeneous bilayer barrier membrane with well-controlled pore size and osteogenesis-promoting ability. The OSA crosslinking significantly improved the structural stability, compressive strength, swelling behavior, and slowed down the biodegradation rate of collagen membranes. Meanwhile, the collagen-based membranes exhibited superior cytocompatibility, osteogenesis-promotion, and barrier function against fibroblasts. Especially, the osteogenic differentiation was most promoted on the membrane with a large pore size (240-310μm), while the barrier function was most improved on the membrane with a small pore size (30-60μm). Then the above two membranes were combined together to obtain a heterogeneous bilayer membrane. This bilayer barrier membrane showed excellent osteogenesis-promoting ability in rats.

Incidental Gallbladder Carcinoma: An Eastern Indian Experience and Necessity of Routine Histopathological Examination after All Cholecystectomy

Introduction: The carcinoma of gallbladder is the most common malignancy of the biliary tract. The incidence of this carcinoma varies geographically. Incidental gallbladder carcinoma is diagnosed during histopathological examination after cholecystectomy due to other reasons. Histopathological examination of all cholecystectomy specimens are very essential to rule out these incidental gallbladder carcinomas. Aim: To this study to estimate the frequency of incidental gallbladder carcinoma in patients undergoing routine cholecystectomy and also to evaluate the necessity of routine histopathological examination after all cholecystectomy. Materials and Methods: A retrospective observational study was conducted in Department of Pathology, Midnapore Medical College and Hospital, West Bengal, India between January 2014 to December 2019 (six years) covering 650 patients who underwent laparoscopic and open cholecystectomy. Patients' demographic data, pathologic results, macroscopic appearance of the specimen, cancer staging were recorded and frequency of incidental gallbladder carcinoma were calculated. Result: Total 650 cholecystectomy specimens due to benign gallbladder disease were received in pathology department. Histopathological examination revealed 18 cases of incidental gallbladder carcinoma which comprised 2.8% of all the cholecystectomies. Among them 13 were female and five were in male with male: female ratio of 1:2.6 and the age ranges from 35 to 68 years. Among 18 cases 10 cases showed invasion upto lamina propria (stage T1a), five) cases had invasion in muscular layer (stage T1b) and three cases showed perimuscular connective tissue invasion (stage T2a). Conclution: The present study observed that the incidence of incidental gallbladder carcinoma in cholecystectomy specimen was little higher range in East Indian population and so routine histopathological examination of all cholecystectomy specimens are recommended.

Cytological Differentiation of Ductal Carcinoma in Situ and Invasive Ductal Carcinoma of the Breast: A Personal View and a Literature Review

Although some find it controversial, it is possible to differentiate breast ductal carcinoma in situ (DCIS) and invasive ductal carcinoma (IDC) using cytology only, with certain limitations. Invasiveness is the consequence of specific biological, i.e. aggressiveness potential of malignant cells, which is different with respect to the pre-existent DCIS, consequentially with different morphology. During the invasion, malignant cells go through multiple morphological changes, losing their epithelial and acquiring mesenchymal features in the fantastic process of epithelial-mesenchymal transition, which explains their morphology in cohabitation with the environment, includes the disruption of intercellular junctions, the increase of mobility and the release of the original epithelium. This mesenchymal-like phenotype supports the migration and invasion of cells, i.e. thus epithelial-mesenchymal transition ensures the tumor dissemination and metastasizing. Therefore, invasiveness can cytologically be “measured” by detecting morphological signs of increase of biological aggressiveness of malignant cells – through the change of their appearance (cytoplasm elongation in malignant squamous cells, i.e. in adenocarcinoma intracytoplasmic lumina, atypical nucleoli, coarsely clumped chromatin, eu-/parachromatin), but also with stromal parameters (disruption of the intercellular matrix, elastin fragments, capillaries endothelium) presented by tumour diathesis, fibroblast proliferation, fragments of elastoid stroma, invasion of connective and/or adipose tissue by groups and individual malignant cells. For the invasion are also very predictive tubular malignant structures, irregular angulated clusters of reduced cohesiveness, absence of benign naked nuclei, polymorph single tumour cells, less myoepithelial cells on tumour groups, fewer microcalcifications and foamy macrophages. Opposite morphological findings suggest DCIS. Even though cytologically we do not see and cannot see the basement membrane, highly likely we can predict the invasion – necessarily and always with the triple-diagnostic approach or clinical-radiological-morphological correlation to every breast lesion, in the representative well cellular sample and with good knowledge of patohistology and cytology

Evaluation of Guided Bone Regeneration in Critical Defects Using Bovine and Porcine Collagen Membranes: Histomorphometric and Immunohistochemical Analyses

Guided bone regeneration (GBR) is a technique used to facilitate bone regeneration, which uses a biocompatible membrane acting as a physical barrier to prevent the adjacent connective tissue from invading the bone defect. The aim of this study was to evaluate and compare the effectiveness of bovine and porcine collagenous membranes as barriers to connective tissue invasion during the repair of critical bone defects in rat calvaria, using histological, histometric, and immunohistochemical analyses. For this study, 72 rats were divided into three groups: clot group (CG), bovine collagen group (BCG), and porcine collagen group (PCG). Analyses were performed on days 7, 15, 30, and 60. The histological results showed that the PCG exhibited bone neoformation starting from day 7, and after 30 days of repair, the surgical defect was completely filled in some animals. For the BCG, there was little bone neoformation activity in the initial periods, and from day 30 onwards, there was an increase in bone neoformation, with a greater increase on day 60. The data obtained in the histometric analysis reveal that, on day 30, the neoformed bone area did not vary greatly between the PCG and the BCG, though both varied from the CG. By day 60, the PCG presented a greater area of neoformation than the BCG. These results were corroborated by the immunohistochemistry results. In view of the results obtained, it can be concluded that all membranes studied in this research promoted GBR.

Morphological and molecular description of a distinct population of Echinorhynchus gadi Zoega in Müller, 1776 (Paleacanthocephala: Echinorhynchidae) from the pacific halibut Hippoglossus stenolepis Schmidt in Alaska.

Echinorhynchus gadi is one of the most widely distributed and commonly described acanthocephalans in marine fishes throughout the world. We provide a detailed morphometric and molecular description of a distinct Alaska population collected from the Pacific halibut Hippoglossus stenolepis Schmidt (Pleuronectidae) compared to those from other hosts and regions, illustrating new features never previously reported. We described new specimens by microscopical studies, augmented by SEM, Energy Dispersive x-ray and molecular analyses, and histopathology. Specimens from Alaska were distinguished from those collected from the other geographical areas in proboscis size and its armature, especially number of hook rows and hooks per row, and length of hooks. The size of the receptacle, lemnisci, and reproductive structures in some other collections also varied from the Alaska material. X-ray scans of the gallium cut hooks depict prominent layering with high Sulfur content for tip cuts and increased calcium and phosphorus content in the base area of the hook. Sections of E. gadi specimens in the host tissue show prominent hook entanglement with subsequent connective tissue invasion also depicting the internal anatomy of certain worm structures not readily seen by other means. Molecular analyses clearly confirmed the identity of our E. gadi sequences. Our Alaska population of the E. gadi complex appears to represent a novel population distinguishable by its distinct morphometrics, geography and host species. We further establish new information on the Energy Dispersive X-ray analysis in our Alaska material for future comparisons with the other siblings and explore genetic relationships among echinorhynchid genera and species.

Aligned Nanofiber-Guided Bone Regeneration Barrier Incorporated with Equine Bone-Derived Hydroxyapatite for Alveolar Bone Regeneration.

Post-surgery failure of dental implants due to alveolar bone loss is currently critical, disturbing the quality of life of senior dental patients. To overcome this problem, bioceramic or bone graft material is loaded into the defect. However, connective tissue invasion instead of osteogenic tissue limits bone tissue regeneration. The guided bone regeneration concept was adapted to solve this problem and still has room for improvements, such as biochemical similarity or oriented structure. In this article, an aligned electrospun-guided bone regeneration barrier with xenograft equine bone-derived nano hydroxyapatite (EBNH-RB) was fabricated by electrospinning EBNH/PCL solution on high-speed rotating drum collector and fiber characterization, viability and differentiation enhancing properties of mesenchymal dental pulp stem cell on the barrier was determined. EBNH-RB showed biochemical and structural similarity to natural bone tissue electron microscopy image analysis and x-ray diffractometer analysis, and had a significantly better effect in promoting osteogenesis based on the increased bioceramic content by promoting cell viability, calcium deposition and osteogenic marker expression, suggesting that they can be successfully applied to regenerate alveolar bone as a guided bone regeneration barrier.

Locally Controlled Diffusive Release of Bone Morphogenetic Protein-2 Using Micropatterned Gelatin Methacrylate Hydrogel Carriers.

In this work, a novel and simple bone morphogenetic protein (BMP)-2 carrier is developed, which enables localized and controlled release of BMP-2 and facilitates bone regeneration. BMP-2 is localized in the gelatin methacrylate (GelMA) micropatterns on hydrophilic semi-permeable membrane (SNM), and its controlled release is regulated by the concentration of GelMA hydrogel and BMP-2. The controlled release of BMP-2 is verified using computational analysis and quantified using fluorescein isothiocyanate-bovine serum albumin (FITC-BSA) diffusion model. The osteogenic differentiation of osteosarcoma MG-63 cells is manipulated by localized and controlled BMP-2 release. The calcium deposits are significantly higher and the actin skeletal networks are denser in MG-63 cells cultured in the BMP-2-immobilized GelMA micropattern than in the absence of BMP-2. The proposed BMP-2 carrier is expected to not only act as a barrier membrane that can prevent invasion of connective tissue during bone regeneration, but also as a carrier capable of localizing and controlling the release of BMP-2 due to GelMA micropatterning on SNM. This approach can be extensively applied to tissue engineering, including the localization and encapsulation of cells or drugs.

IL‐33/ST2L mediated ADAMTS10 activation regulate retinal endothelial cell sprouting and neovascularization in a murine model of hypoxia‐induced retinopathy

Pathological retinal neovascularization is a clinical manifestation of various proliferative retinopathies, including retinopathy of prematurity (ROP), diabetic retinopathy, and the wet form of macular degeneration. A characteristic feature of these conditions is the presence of hypoxic areas and over‐expression of the proangiogenic vascular endothelial growth factor (VEGF). Treatments of these neovascular diseases using laser or anti‐VEGF therapies not only induce various local and systemic side effects but also are only partially effective. Here, using a murine model of oxygen‐induced retinopathy, we found that either intravitreal injections of IL‐33 siRNA or genetic deletion of IL‐33 resulted in reduced neovascularization with no significant changes in the avascular area. These findings suggest a role for IL‐33 in pathological neovascularization with little or no effect on the normal retinal repair. Interestingly, we observed that along with IL‐33 activation, hypoxia also induces expression of ST2 transmembrane receptor (ST2L), both at mRNA and protein levels, with little or no effect on secretory ST2 (sST2) levels. Our in vitro experiments using human retinal microvascular endothelial cells as a model suggest the importance of IL‐33/ST2L‐signaling on endothelial cell migration, tube formation, and sprouting. Besides it, our in vitro and in vivo findings provide evidence that IL‐33/ST2L‐signaling via ADAMTS10 activation facilitates sprout formation and invasion of connective tissue through controlled degradation of extracellular matrix proteins (ECMs). These results strongly suggest that IL‐33/ST2L‐signaling plays a key role in retinal neovascularization and thus represents a new pharmacological target for the treatment of diseases where excessive neovascularization is the underlying pathology.Support or Funding InformationThe research is supported by NIH EY029709 grant..

Effect of Point Mutation in the Growth Differentiation Factor 9 Gene of Oocytes on the Sterility and Fertility of Awassi Sheep.

Growth differentiation factor 9 (GDF9) plays a critical role in ovarian follicular development and ovulation rate. The present study aimed to investigate the correlation between the single-nucleotide polymorphism (SNP) of the GDF9 gene and reproductive performance variables, such as fertility and sterility in Awassi sheep. Forty pairs of ovaries from a total of 40 slaughtered Iraqi Awassi ewes were used in this study. Twenty of the ovaries were collected from sterile ewes and the other 20 ovaries were taken from fertile ewes for genomic DNA extraction, polymerase chain reaction, and sequencing to detect GDF9 gene polymorphism. Follicles and oocytes of all the 40 ovaries were evaluated and compared with the results of genotyping. Furthermore, histopathological and microscopic evaluations were performed for 40 ovarian tissues of the two groups. The sequence analysis revealed that exon I had three SNPs, including T(114)C, G(129)R, and G(199)A. The first two SNPs were silent mutations and the last mutation was missense responsible for the substitution of glutamic acid with lysine at position 67. The current study showed a significant increase (P&amp;le;0.01) in GG, AA, CC, GA, and GG genotypes at G(129)R, G(199)A, T(114)C, G(129)R, and G(199)A loci, respectively. Moreover, the TT genotype in locus T(114)C was recorded to significantly augment (P&amp;le;0.05) in the fertile ewes. Mutant GA genotype of the G(129)R locus led to a significant (P&amp;le;0.05) increase in the percentage of follicles (4-8 mm) and oocytes number, compared to wild GG. On the other hand, a significant decrease was recorded in the mutant AA genotype in G(199)A, compared to wild GG. Differences between CC and TT genotypes at T(114)C locus were not significant. Histopathological examination revealed hypoplasia in the ovarian tissue of sterile ewes accompanied by fibrous connective tissue invasion and follicles degeneration. However, in the fertile ewes, the ovarian tissues were normal with the presence of numerous corpus albicans and degenerative corpus luteum. According to the findings of this study, the homozygote mutation in fertile ewes minimized the number of follicles and oocytes leading to sterility, while the heterozygote mutation was reported in the fertile Awassi ewes.

Carcinogenic effect of potassium bromate on tongue of adult male albino rats

Potassium bromate (KBrO3), a strong oxidizing agent, is mainly used as a flour improver; it is classified as B2 (probable human) carcinogen and health organizations start banning it. However, it is still used in bakeries in large amounts. The aim of this study was to investigate the effect of KBrO3 administration on the tongue of adult male albino rats. Sixty adult male albino rats weighting ~200 gm were divided equally into threegroups: control, experimental group I (gp I), and experimental group II (gp II). Control group received distilled water and the experimental gps. received 62 and 123 mg\kg KBrO3, respectively, dissolved in distilled water orally on a daily basis for 2 and 4 months. Histopathological examination of specimens in experimental groups revealed dysplastic and carcinogenic changes that were dose- and time-dependent to end in the epithelial invasion of connective tissue. The immunohistochemical results showed a significant increase in the immunoreactivity of PCNA in KBrO3 treated groups compared to the control group. In conclusion, KBrO3 long-term administration has a carcinogenic effect, so it is considered as a risk on public health.

Design of a biodegradable UV-irradiated gelatin-chitosan/nanocomposed membrane with osteogenic ability for application in bone regeneration

Guided bone regeneration membranes are used in oral surgery to protect the site of a lesion exposed to connective tissue invasion which, in turn, prevents new bone formation. Although non-degradable and degradable materials have been applied in clinical treatments, biodegradable membranes have the advantage that they do not require a secondary surgical procedure to be removed. However, they have a very low mechanical strength. As biodegradable membranes, biomaterials based on gelatin-chitosan have gained importance in clinical applications due to their unique properties. Gelatin contains RGD-like sequences, promoting cell adhesion/migration, and it can be blended with chitosan, which allows the immobilization of nanoparticles. In this work, we designed a new gelatin-chitosan polymeric membrane which contains hydroxyapatite and titania nanoparticles as two very well-documented osteoconductive materials. UV radiation was used as a non-toxic cross-linking agent to improve the thermophysical/mechanical characteristics and to control the biodegradability of the nanocomposed membrane. The microstructure, thermophysical and mechanical properties of the UV-irradiated material were studied by scanning electron microscopy, differential scanning calorimetry and Young's modulus, respectively. The in vitro biocompatibility of the new nanocomposite was evaluated by cell adhesion and proliferation assays. The osteoconductive ability was determined by an alkaline phosphatase production assay using mouse embryonic fibroblast (MEF) cells. The results show a homogeneous material with an appropriate distribution of nanoparticles. Cross-linking by UV radiation improved the mechanical and biological performance of the membrane. The presence of two osteoconductive nanoparticles, such as titania and hydroxyapatite, increased the osteogenic potential of the gelatin-based material in vitro, which confers a biological function, in addition to functioning as a physical barrier. The material obtained herein represents a good alternative to current guided bone regeneration membranes, with high potential for use in oral/orthopaedic applications in patients.